DIY 18650 battery power bank and charger box with LCD display for custom portable power

This versatile mobile power box provides a practical solution for users seeking control over their portable power supply. By accepting up to four standard 18650 lithium-ion batteries, which are not included, it allows you to determine the final capacity and quality of your power bank, effectively avoiding the risks and troubles associated with battery transportation. The unit serves a dual purpose: it functions as a customisable external battery pack for charging devices like mobile phones and tablets, and as a dedicated charger for your 18650 cells. Its compact dimensions of 100 mm wide by 84 mm tall by 26 mm deep make it a portable option, and it is available with a plastic casing in either black or white to suit your preference.

Features and Construction

The power box is built around a flexible DIY principle, putting the choice of battery capacity and quality firmly in your hands. Its construction centres on reliable, independent circuitry designed for safe operation.

Material and Build

The main housing is made from plastic, offered in a choice of black or white finishes. Internally, the board features a protection chip that automatically identifies and cuts power to any circuit with reversed polarity, displaying an empty battery level on the LCD screen for that cell. This safeguard ensures a reversed cell does not affect the normal operation of the other independent circuits, allowing the remaining batteries to charge and discharge as intended.

Size and Practical Fit

With external measurements of 100 x 84 x 26 mm, the power box maintains a compact profile suitable for carrying in a bag or jacket pocket. This size efficiently houses the necessary circuitry, dual input and output ports, and the LCD display while leaving ample internal space for the four 18650 batteries you install. The design prioritises a balance between portability and functionality for a custom power solution.

Uses and Placement

This product is designed for users who value customisation and need reliable power on the go, whether for daily use or specific projects.

Event or Professional Use

For photographers, event staff, or tradespeople away from mains power, this DIY power bank offers a tailored energy reserve. You can select high-capacity or high-drain 18650 batteries suited to your professional equipment's demands. The dual outputs allow you to keep a phone and a tablet charged simultaneously during a long shoot or workday, while the LCD screen provides clear, real-time monitoring of your remaining power, which is crucial for planning.

Everyday Home Use

At home, it acts as a centralised charging station and a way to repurpose old 18650 batteries from other devices. Families can use it to charge multiple phones or tablets overnight from a single compact unit. The DIY aspect is particularly useful for tech enthusiasts or those wanting to avoid pre-built power banks with non-replaceable or overstated battery cells, as you control the quality and capacity directly.

Benefits and Buying Value

The core value of this power box lies in its flexibility, transparency, and the practical advantages of its specific features.

Reuse and Low Maintenance

The design encourages the reuse of existing 18650 batteries, promoting a more sustainable approach to portable power. The independent circuits and clear LCD display simplify maintenance by allowing you to monitor each battery's health individually. If one cell fails or is inserted incorrectly, the protection circuit isolates it without disabling the entire unit, making troubleshooting straightforward and reducing downtime.

Why Choose This Product

This product stands out for putting you in control of your power supply's most critical component: the battery. It lets you reject false capacity claims and low-quality inferior batteries by choosing your own cells. The combination of dual outputs for simultaneous device charging, dual inputs for convenient recharging, and the safety of reverse polarity protection offers a level of utility and peace of mind that fixed-capacity power banks often lack, all within a compact and user-monitored package.